Tanzanite, the Gemstone of the Century
Tanzanite, now one of Decembers birthstones, is among the most rare and unusual gemstones to be discovered in recent years. It was first discovered in 1967 and although the rich lavender/blue color is so striking, the gem itself is actually the mineral zoisite which occurs in yellow, pink and green and is found more commonly. This type of zoisite is unique, because in its shades of blue and lavender, it is only found in the Merelani Hills in north Tanzania. With this being the only known location, there is a time limit on the mining in the area, which only covers about four miles.
Tanzanite Colors
Tanzanite occurs naturally in a dark brown color and it is believed that the Massai herdsmen originally discovered it in the blue shades as a result of a lightning strike causing extreme heat to loose crystals lying on the ground. This discovery attracted the interest of Manuel Desouza, a Portuguese geologist who found that when treated with extreme heat (600c) the Tanzanite crystals change permanently to the rich lavender/blue with trichroic qualities which show shades of red, pink and lilac when viewed from different angles.
The new gem was given its distinctive name by the famous jewelers, Tiffany’s as a tribute to its location. They promoted it worldwide and it is now one of the top five best selling precious stones. Beautiful though it is, Tanzanite is nothing like as robust as the harder gemstones, such as diamonds, rubies and sapphires. On the Moh’s scale, diamond is the hardest at 10, rubies and sapphires are 9 while Tanzanite is only 6.5, so care must be taken if it is not to become damaged. Do not attempt to do any physical work when wearing a Tanzanite ring, even cooking or washing up is too risky and it should never be placed it in an ultrasonic cleaner. There is a limited time for new Tanzanite gemstones to be extracted, so with care, a item of jewelry set with this gem can easily increase in value and become an heirloom piece for future generations.